Why would you want to keep the save files if you're getting rid of the game?
Because the average 3DS owner has less storage space on their 3DS than there is stuff to store on the 3DS. Why wouldn't people want to be able to remove content from their 3DS to free up space without erasing everything that they've done so far?
Ah I c, I'll probably try that next time. Well luckily, I forgot about the demos and the likes that were taking phenomenal space in my sd card, so I just deleted those instead. Owned most of the games that I had demo for anyways.
According to Wikipedia, you don't exist! Official official. Officially